Nutrition for ice diving

[SeaHorse81]

A friend of mine is going ice-diving this weekend. The anticipated agenda is to do two dives, approximately 30 minutes each. Water temp should be around 38 degrees, air temp around 22 degrees; dry suit, of course and warming facilities presumably immediately available.

My question is what such a diver should be doing as far as caloric intake to properly support the body's needs for this activity. What kinds of food and how many calories are advisable the day before (if applicable) and the day of diving?

How long before the first dive does it make sense to load on extra calories, given what amount of time those calories remain available as ready-use energy before being converted to fat?

If the body's needs exceed intake due to the demands of the dives, can the body get the needed additional energy in real time from fat reserves?

Does ice diving create physiological demands that require special nutritional care afterward?

Thanks very much for any information on this. I work with food issues for a living, but don't know how much of my knowledge translates to unusual conditions like this.

 

[Brian Sharpe]

Caveat - I'm not an ice diver (perhaps this question would be better posed in either advanced or tech diving forum) but caloric intake for cold weather exercise is something I've looked as I run outdoors all year 'round.

The bottom line, as far as I've been able to determine, is that with proper environmental protection (layered clothing for a run or drysuit with suitable undergarments dry gloves hood etc) is that the energy needs for the task at hand are independent from the outside temperature. There was a long standing myth that exercise in the cold required a higher caloric output leading to faster weight loss - not true.

How readily one can access energy stored in fat is largely a measure of physiological adaptation it's hard to answer that question.

With the exception of humping gear to and from the dive site diving is not a calorie intensive activity (I'd be extremely worried if I dived with some who managed to reach their VO2 max or lactate threshold while diving) - just having a good balanced breakfast and a between dive snack (and warm non-alcoholic drink?) should be sufficient.

 

[Kingpatzer]

The big thing is just going to be caloric intake. I just recommend folks have a good breakfast the day of the dive. Particularly if the site is not going to be prepped before hand. Cutting the hole, hauling the ice out of the hole, putting in ice screws, humping gear, putting up tents, and so on all take energy.

No need to pig out, but a pocket full of gorp goes a long way (at least in my experience).

I'm actually typically more concerned about people being properly rested. It can be a very long day for students and instructors and showing up fully rested is very important. For several days prior to the dive get full night's sleep -- that's 7-8 hours or more, not 5 or 6!

 

[SeaHorse81]

Thanks so much for your replies. I had no idea where to place this thread, as ice diving didn't seem to be included in the technical section.

I'm asking because the instructor who certified my friend for ice diving apparently emphasized the need for 5000-7000 extra calories for a day of ice-diving, with major loading beginning the day before. This doesn't really make sense to me since, as you pointed out, a properly attired diver won't get extremely cold, and diving isn't overly strenuous (though the extra work with ice-diving is somewhat demanding, I don't see it amounting to many thousands of extra calories).

I don't want to assume the instructor was misleading or was himself misinformed, so I wondered if there's something special about the physiological demands of ice-diving that really requires what seems like such drastic measures.

Other thoughts?

 

[Kingpatzer]

(though the extra work with ice-diving is somewhat demanding, I don't see it amounting to many thousands of extra calories).

Thousands? Probably. 5,000? Probably not.

 

[rcs9250]

I have been ice diving for a couple years. I have never done anything special. Eat a good breakfast. I have winter camped for many years . With that you want to eat (snack) almost continuosly to keep the fire going. Some folks take a stick of butter to bed with them and chomp on it during the night . Fat is good for the slow burn to keep that fire going.
As with all diving your primary concern is hydration. Winter hydration is even more important since the cold dry air robs you of water vapor with each breath. Keep a water bottle in your pocket and sip/drink often.
Proper food without water is like a candle but no match.
As mentioned previously, GORP is an excellent source of nutrition.

 

[SeaHorse81]

Thousands? Probably. 5,000? Probably not.

Especially since my friend will not, to my knowledge, be doing any ice-chopping or serious site setup. I think his biggest demands will be wrestling with equipment and the diving, itself.

This huge-calorie thing is starting to sound more and more suspect.

I'm embarassed to have to ask, what is GORP?

 

[Kingpatzer]

I'm embarassed to have to ask, what is GORP?

It's what outdoors folks, particular campers and backpackers, call trail mix.

Trail mix - Wikipedia, the free encyclopedia

 

[SeaHorse81]

Oh, I see. Yep, that looks like it would be the perfect fuel for this. Thanks!

 

[rongoodman]

I'm embarassed to have to ask, what is GORP?

Good Old Reliable Peanuts